Translocation of phospholipase A2 from cytosol to membranes in rat brain induced by calcium ions

https://doi.org/10.1016/0006-291X(90)92117-IGet rights and content

Abstract

Phospholipase A2 (PLA2) activities were found in the cytosolic fractions of rat brain. Using the gel filtration chromatography, two major peaks of PLA2 activities were demonstrated: PLA2-H (200 – 500 kDa) and PLA2-L (100 kDa). PLA2-L was active at both neutral and alkaline pH and absolutely required Ca2+ for the activity, while the activity of PLA2-H was detected only at alkaline pH and independent of Ca2+. The activation of PLA2-L by Ca2+ was biphasic; the first observed at 1 – 100 μM Ca2+ and the second at 10 mM Ca2+. In the reconstitution system of partially purified PLA2-L and synaptosomal membranes from rat brain, PLA2-L associated with the membranes in a Ca2+-dependent manner. The association was completed within 5 – 10 min at 25°C both at 10 μM and 1 mM Ca2+, though amount of PLA2-L translocated was dependent on Ca2+ concentrations. These results suggest that Ca2+ promotes the translocation of the cytosolic PLA2-L to membranes where phospholipids, substrate of PLA2, are present.

References (22)

  • S. Horiguchi et al.

    Eur. J. Pharmacol

    (1986)
  • Y. Watanabe et al.

    Brain Res

    (1986)
  • A.C. Maroney et al.

    J. Biol. Chem

    (1989)
  • A. Baba et al.

    J. Biol. Chem

    (1989)
  • R. Cornell et al.

    Biochim. Biophys. Acta

    (1987)
  • W.C. Puijk et al.

    Biochim. Biophys. Acta

    (1977)
  • J. Ishizaki et al.

    Biochem. Biophys. Res. Commun

    (1989)
  • R.M. Balow et al.

    J. Biol. Chem

    (1986)
  • J.Y. Channon et al.

    J. Biol. Chem

    (1990)
  • M. Waite
  • B. Sammuelson et al.

    Ann. Rev. Biochem

    (1978)
  • Cited by (0)

    View full text